Note: Descriptions are shown in the official language in which they were submitted.
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LIlVIE INDEPENDENT CEIVIENTITIOUS MIXTURES
FIELD OF INVENTION
THIS INVENTION relates lime independent cementitious mixtures and to a method
of
fonning concrete which is not reliant upon the inclusion of calcined lime.
The present invention has particular application to substantially lime-free
cementitious
mixtures for use in applications in which lime-based cementitious mixtures
have a tendency to
corrode. The invention also relates to cementitious mixtures in respect of
which the contribution
of the set cementitious mixture to the corrosion of iron-based reinforcing
elements embedded in
the concrete is substantially ameliorated.
In the art, the terms "cement" and "concrete" are used somewhat loosely. In
this
specification, unless the context requires otherwise, the term "cement" is
used to refer to the
powdered constituents when mixed together prior to being activated to form
concrete. Unless the
context requires otherwise, the term "concrete" is used to refer to a
composite material including
cement after the addition of water to make it set as well as the material once
it has set. Concrete
normally also includes aggregate and cement binder to blended with water to
form a composite
material.
BACKGROUND ART
Cementitious mixtures traditionally include calcined lime and/or other similar
pozzolanic
material for binding of or with other constituents to form concrete. Portland
cement is a
particularly common cement used to make structural concrete which is normally
reinforced. Lime
is a very common constituent in cement, Portland cement being typically formed
from limestone,
clay and gypsum. However, notwithstanding that gypsum is a sulfur compound,
lime in concrete
may be attacked by sulfur or sulfurous materials. As a result, in some
environments, the presence
of calcined lime may adversely affect the structural integrity of concretes
having calcined lime in
their formulations.
Traditional cementitious mixtures involve compounds of alkaline earth metals.
Lime has
long been used, and a magnesia cement has been proposed for use in the
agglomeration,
aggregation, hardening and moulding of mineral, vegetable or animal substances
by means of
magnesium oxychloride. A later development is a proposal to blend magnesia
with a metallic
oxide and phosphate. However, the only oxides suggested are those of iron.
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The present invention aims to provide lime independent cementitious mixtures,
and a
method of forming concrete from cementitious mixtures substantially free of
calcined lime which
alleviate at least one of the abovementioned problems of the prior art. Other
aims and advantages
of the invention may become apparent from the following description.
DISCLOSURE OF THE INVENTION
With the foregoing in view, the present invention in one aspect resides
broadly in a lime
independent cementitious mixture including:
an iron oxides constituent comprising one or more oxides of iron; and
an activator selected from one or more metal non-chloride salts which may form
one or
more megalithic molecules with the iron oxides constituent when co-activated
with water.
In another aspect, the present invention resides broadly in a lime independent
cementitious mixture including:
an iron oxides constituent comprising one or more oxides of iron; and
an activator selected from one or more metal phosphates which may form one or
more
megalithic molecules with the iron oxides constituent when co-activated with
water.
In another aspect, the present invention resides broadly in a lime independent
cementitious mixture including:
an iron oxides constituent comprising one or more oxides of iron; and
an activator selected from one or more metal nitrates which may form one or
more
megalithic molecules with the iron oxides constituent when co-activated with
water.
In another aspect, the present invention resides broadly in a lime independent
cementitious mixture including:
an iron oxides constituent comprising one or more oxides of iron; and
an activator selected from one or more non-alkaline earth metal salts which
may form one
or more megalithic molecules with the iron oxides constituent when co-
activated with water.
In another aspect, the present invention resides broadly in a lime independent
cementitious mixture including:
an iron oxides constituent comprising one or more oxides of iron;
an activator selected from one or more non-alkaline earth metal salts and one
or more
magnesium and/or aluminium non-chloride salts which may form one or more
megalithic
molecules with the iron oxides constituent when co-activated with water.
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In another aspect, the present invention resides broadly in a lime independent
cementitious mixture including:
an iron oxides constituent comprising one or more oxides of iron;
a silicates constituent comprising one or more calcined metal silicates; and
an activator selected from one or more metal salts which may fonn one or more
megalithic molecules with the iron oxides and/or silicates constituents when
co-activated with
water.
In another aspect, the present invention resides broadly in a lime independent
cementitious mixture including:
an iron oxides constituent comprising one or more oxides of iron;
a silicates constituent comprising one or more calcined metal silicates; and
an activator selected from one or more metal non-chloride salts which may form
one or
more megalithic molecules with the iron oxides and/or silicates constituents
when co-activated
with water.
In another aspect, the present invention resides broadly in a lime independent
cementitious mixture including:
an iron oxides constituent comprising one or more oxides of iron;
a silicates constituent comprising one or more calcined metal silicates; and
an activator selected from one or more non-alkaline earth metal salts which
may form one
or more megalithic molecules with the iron oxides and/or silicates
constituents when co-activated
with water.
In another aspect, the present invention resides broadly in a lime independent
cementitious mixture including:
an iron oxides constituent coniprising one or more oxides of iron;
a silicates constituent comprising one or more calcined metal silicates; and
an activator selected from one or more non-alkaline earth metal salts and one
or more
magnesium and/or aluminium non-chloride salts which may form one or more
megalithic
molecules with the iron oxides and/or silicates constituents when co-activated
with water.
Preferably, the iron oxides constituent is selected from iron ores including
taconite,
magnetite and hematite and from mill scale, mill rust, and red mud from
bauxite. Preferably, the
iron oxides constituent is calcined. Preferably, the iron oxides constituent
comprises from 20% to
50% by weight of the mixture.
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In another aspect, the present invention resides broadly in a lime independent
cementitious mixture including:
a silicates constituent comprising one or more calcined metal silicates; and
an activator selected from one or more metal salts which may form one or more
megalithic molecules with the silicates constituent when co-activated with
water.
In another aspect, the present invention resides broadly in a lime independent
cementitious mixture including:
a silicates constituent comprising one or more calcined metal silicates; and
an activator selected from one or more metal non-chloride salts which may form
one or
more megalithic molecules with the silicates constituent when co-activated
with water.
In another aspect, the present invention resides broadly in a lime independent
cementitious mixture including:
a silicates constituent comprising one or more calcined metal silicates; and
an activator selected from one or more non-alkaline earth metal salts which
may form one
or more megalithic molecules with the silicates constituent when co-activated
with water.
In another aspect, the present invention resides broadly in a lime independent
cementitious mixture including:
a silicates constituent comprising one or more calcined metal silicates; and
an activator selected from one or more non-alkaline earth metal salts and one
or more
magnesium and/or aluminium non-chloride salts which may form one or more
megalithic
molecules with silicates constituent when co-activated with water.
Preferably, the non-chloride salts are selected from magnesium and aluminium
non-
chloride salts. In such form, ammonium non-chloride salts may be included.
Preferably, the
silicates constituent includes meta zirconium silicate. Preferably, the
silicates constituent includes
magnesium aluminium silicates. Preferably, the mixture includes from 5% to 30%
magnesium
carbonates and oxides (with or without a calcium component) with 10% to 60%
aluminium
oxides. Preferably, the mixture includes a silicates constituent as
hereinbefore described and
comprising from 10% to 30% meta zirconium silicate and 5% to 20% other
pozzolan. Preferably,
the materials are selected from mineral ores such as magnesite, brucite,
dolomite, bauxite and/or
kaolin. Preferably, the mixture includes from 1 to 25% sodium borate
decahydrate and 10% to
25% nitrate and or phosphates of ammonia, calcium and/or potassium which have
been
sequestered with 1% to 5% magnesium distearate salt. Preferably, the activator
includes
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magnesium sulfate, aluminium sulfate, magnesium fluorosilicate, sodium
chloride, calcium
chloride, ferric chloride, and/or magnesium chloride.
It will be appreciated that the constituents and the activator are comminuted
and/or
triturated to a size suitable for concrete manufacture. It is believed that
the one or more
megalithic molecules may be formed by metathesis or the like between the iron
oxides and/or
silicates constituents and the activator when co-activated by the addition of
water to the dry
mixture, however, the invention is not necessarily limited to mixtures which
undergo such a
process.
The iron oxides constituent may be selected from iron ores such as taconite,
magnetite,
hematite or such like, but may also be selected from mill scale or rust, red
mud from bauxite as
may be extracted in alumina refining and such like. The iron ores may be
selected from lower
grade ores than might be required for iron and steel production. Such
materials may be calcined if
required.
The silicates constituent preferably includes meta zirconium silicate, but may
include
other pozzolan such as silica fume for example to assist in densifying and/or
strengthening the
concrete. Other magnesium aluminium silicates may also be included.
In such form that the iron oxides constituent comprises from 20% to 50% by
weight of the
mixture, it is preferred that the silicates constituent comprises from 10% to
30% meta zirconium
silicate and 5% to 20% other pozzolan. The mixture also preferably includes
from 5% to 30%
magnesium carbonates and oxides (with or without a calcium component) with 10%
to 60%
aluminium oxides. These materials are preferably selected from mineral ores
such as magnesite,
talc, brucite, dolomite, bauxite and/or kaolin.
It is believed that there may be benefits in using fly ash for the alumina
component due to
its properties of fineness and silica content. The UBC (unbumt carbon) content
of fly ash, such
as that which may be found in "bottom" fly ash may also provide an advantage
in strength and/or
density of the concrete formed in accordance with the invention. Other
magnesium aluminium
silicates may be sourced such as from other waste streams and/or different ore
bodies and added
to or provided with the mixture in appropriate component proportions.
In a further preferred form, the mixture includes from 1 to 25% sodium borate
decahydrate and 10% to 25% nitrate and or phosphates of ammonia, calcium
and/or potassium
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which have been sequestered with 1% to 5% magnesium distearate salt. Other
metal stearates
may also be used, and it will be appreciated that different metal stearates
would lilcely have
different sequestering effects.
The activator may include magnesium sulfate, aluminium sulfate, magnesium
fluorosilicate, sodium chloride, calcium chloride, ferric chloride, and/or
magnesium chloride. A
reaction retarding agent such as oxalic acid, tartaric acid and or sodium
tetraborate may also be
included for slowing down the setting of the concrete. Retarding agents may
also be selected
from naphthalene and melamine sulfonate superplasticisers. Wetting and/or
plasticising may also
be achieved by including acrylic acid polycarbonate based superplasticisers.
BRIEF DESCRIPTION OF THE EXAMPLES
In order that the invention may be more readily understood and put into
practical effect,
reference will now be made examples which illustrate the invention in one or
more preferred
forms. In the examples, cementitious mixtures not based on calcium were
tested. However, small
proportions of lime could be tolerated as a contaminant, or limestone could be
used as an
aggregate extender. There were two types of limestone free cementitious
mixtures - iron oxide
based and silicate based. There were two methods of production - batching pre-
processed metal
oxides or calcining and crushing. There were three alternative methods of
activation based on the
selected activator - phosphate, sulfate or chloride.
DETAILED DESCRIPTION OF THE EXAMPLES
EXAMPLE SET 1- Iron Oxide Cementitious Migtures
A first example in this set was formulated using the following constituents:
Fe as filings and powdered metallic iron;
Fe304 as iron ore (magnetite) and waste stream mill scale;
Fe203 as iron ore (hematite) and industrial waste streams;
Fe3PO4 as ferric orthophosphate;
FeC13 as iron trichloride;
ZrSiO2 as waste stream amorphous zirconium silicate;
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Si02 as crushed silica and/or (amorphous) silica fiame;
A1203 as bauxite', dolomite2, kaolin3 and waste stream fly ash4 (bottom ash is
suitable);
H3PO4 as mono potassium dihydrogen phosphateAl, ammonium dihydrogen phosphateA
2,
aluminium phosphateA3, sodium diphosphateA 4, zinc phosphateA5, zirconium
phosphate^6
ferric orthophosphateA 7 and phosphate rocO;
H2SO4 as aluminium sulfate', diarnmonium sulfate2, and ferrous sulfate
heptahydrate3;
H2CO3 as sodium bicarbonate or potassium bicarbonate;
COOHCOOH as ethanedioic (oxalic) acid;
COOHCH(OH)CH(OH)COOH as tartaric acid;
MgO as magnesite*1, calcined MgO*2 , dead burnt MgO*3 and electro-fused MgO*4;
MgSiF6 as magnesium hexafluorosilicate hexahydrate;
IVIg(C18H3502)2 as octadecanoic magnesium stearic acid;
MgC12 magnesium dichloride hexahydrate; and
Na2B4O7 as sodium tetraborate decahydrate.
Set Time Control
Combinations of the four stages of magnesium oxide are used to control set
speed and
help develop high early strength in much the same way that the combination of
CaSO4 and C3A
activate calcium based cements. Magnesium carbonate, caustic magnesia or
calcined magnesium
cause the set to commence within 30 seconds to 5 minutes. Dead burnt magnesium
extends the
set time from 30 minutes to 4 hours. Electro-fused magnesium or part thereof
controls set times
between 5 minutes and 30 minutes.
Activator
A catalyst or initiator is required to stimulate a reaction required
(typically exothermic) to
produce polymerisation, gelling and/or crystallisation that resulted in the
material forming a hard
monolithic mass. For the same reason that gypsum is added to calcium cement,
the cement of the
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example may be initiated with a combination of MgO, ZnO or PbO and KPO4a
NHPO4,
Al2(SO4)3, MgC12, FePO4, FeC13, NaBO4.
Cohesion/Rheology Modifiers
Further set time extenders include Na2B4O7, MgSiF6, H2C204 and C4H606 but
these
components also change cohesive and rheological properties and can be
formulated to suit
various applications.
The cohesion/rheology modifiers can be provided in the following ranges (by
weight):
NaaB4O7 - 0 to 25;%
MgSiF6 - 0 to 25%;
H2C204 - 0 to 10%;
C4H606 - 0 to 10%.
Based on the above criteria, a series of "iron cement" formulations were
tested, each test
being allocated a test number as "Fe8-XXa" where "XX" refers to the test
number, and "a" refers
to the kind of initiator used where "p" refers to phosphate, "s" refers to
sulfate, and "c" refers to
chloride. The tests are set out hereunder.
Fe8-QQp
Ingredients:
Constituent Content (% by weight) %Latitude
Fe304 35 0 to 75
Fe203 0 0 to 75
Fe 0.5 O to S
Si02 2 0 to 25
4A1203 10 5 to 50
A1HPO4 15 0 to 35
A7HPO4 3 0 to 35
*3MgO 18 0 to 50
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4Mg0 4.5 0 to 50
MgSiF6 0.4 0 to 5
Mg(C18H35O2)2 0.6 0 to 5
NaaB4O7 2 0 to 10
ZrSiO2 9 0 to 50
TOTAL 100
Method:
An 0.01 g resolution balance was used to measure the dry components into a
mixing
beaker. A wooden spatula was used to mix water in with the dry ingredients
until the mix became
plastic. The mixture was then stirred for a further 3 minutes.
The contents of the beaker were transferred into a mould and allowed to set
hard to form
an iron cement test piece "Fe8-OOp" for a period of 4 hours before being
demoulded.
Result:
Within the first 15 minutes, gelling had commenced and a small amount of heat
was
noted due to the accelerated setting caused by the (replaceable) percentage of
MgO*4
During an observation period of 3 days, the test piece "Fe8-OOp" gained very
high
strength, and demonstrated very high magnetic attraction. No shrinkage was
noted.
Conclusion:
With the ability to control the set speed of this cement, it should be
possible to produce
extreme strength concrete with short optimum strength times. Other properties
such as
waterproof, sulfate and chloride resistance are fiu-ther enhanced by the very
high achievable
density.
Fe304 (magnetite) can be replaced by Fe203 (hematite) but it was found that a
small
percentage of Fe (iron) helps to densify the set structure. The percentage
range is 0 to 5%.
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Tests
The following formulae have been reduced to the reactive ingredients and have
been
carried out for the purpose of determining the latitude of quantities (+ & -)
that achieve a
solidification reaction while still retaining the properties of the original
purpose. It is also noted
that solidification occurs outside the claimed parameters, but would only be
suitable for
solidification of waste sludge such as paint or other polymer clay based
industrial waste.
Fe8-01p Low Iron and Low Initiator
Ingredients:
Constituent Content (% by weight)
Fe304 20
A1203 60
A 1HPO4 10
MgO 10
TOTAL 100
Method:
An 0.01 g resolution balance was used to measure the dry components into a
mixing
beaker. A wooden spatula was used to mix water in with the dry ingredients
until the mix became
plastic and then the mixture was stirred for a further 3 minutes.
The contents of the beaker were transferred into a mould and allowed to set
hard for a
period of 4 hours before being demoulded.
Result:
Extra water had to be added to compensate the absorption of the fly ash, but
no bleed was
noted. No exothermic heat was noticed during the setting. During the next 3
days, "test Fe8-0lp"
remained in a low but slowly gaining strength state, and demonstrated slight
magnetic attraction.
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Conclusion:
AlSiOa in the form of fly ash, is an excellent pozzolan that is capable of
becoming a
cement component when blended with other cement forming ingredients. While
this material
demonstrates utility in cementitious mixtures of the present invention, it
should be appreciated
that its inclusion increases water requirements and subsequently develops
lower strength when
used in higher ratio to the iron oxide component. This issue may be addressed
with the use of a
suitable plasticiser such as a carboxylated acrylic copolymer that produces
steric repulsion, rather
than electrostatic repulsion as produced by sulfonated condensates.
Fe8-02n High Iron and Low Initiator
Ingredients:
Constituent Content (% by weight)
Fe304 60
A1A12O3 20
HPO4 10
MgO 10
TOTAL 100
Method:
An 0.01 g resolution balance was used to measure the dry components into a
mixing
beaker. A wooden spatula was used to mix water in with the dry ingredients
until the mix became
plastic. The mixture was then stirred for a further 3 minutes.
The contents of the beaker were transferred into a mould and allowed to set
hard for a
period of 4 hours before being demoulded.
Result:
No heat became obvious during setting. During the three-day observation, "test
Fe8-02p"
maintained low strength state for the first day, then appeared to gain
strength rapidly over then
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next two days and demonstrated very high magnetic attraction. The surface
appeared to be
slightly dusty, indicating there was more Fe304 then could react before the
initial set.
Conclusion:
Fe304 is an effective cement forming component, but requires a greater
quantity of the
combined initiator HPO4 and MgO if the gel time requirement is shorter than 15
minutes.
Fe8-03s Iron with a Sulfate Initiator
Ingredients:
Constituent Content (% by weight) %Latitude
Fe304 40 15 to 75
Fe 0 O to 5
Si02 0 0 to 25
A1203 10 5 to 50
A 3HP04 3 0 to 35
1HZS04 15 0 to 25
3HaSO4 2 0 to 35
*3MgO 30 10 to 75
MgSiF6 0 0 to 5
2Mg(C18H3502) 0 0 to 5
Na2B4O7= 10H20 0 0 to 10
ZrSiO2 0 0 to 50
TOTAL 100
Method:
An 0.01 g resolution balance was used to measure the dry components into a
mixing
beaker. A wooden spatula was used to mix water in with the dry ingredients
until the mix became
plastic. The mixture was then stirred for a further 3 minutes.
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The contents of the beaker were transferred into a mould and allowed to set
hard for a
period of 4 hours before being demoulded.
Result:
"Test Fe8-03s" gelled in 10 minutes and set very quickly with slight but
noticeable
exothermic heat. High strength was apparent within a few hours and high
magnetic attraction was
demonstrated.
Conclusion:
Sulfates work as effectively to initiate a set as phosphates. Control in set
time was not
determined, however the strength and magnetic attraction were still very high.
(There was also an
indication that external sulfates in the form of gas or aqueous solution
contact may strengthen or
case-harden a compound or concrete made from this cement.)
EXAMPLE SET 2- Zirconium Silicate Cementitious Migtures
The cement based on zirconium silicate was found to posses exceptionally high
refractory
qualities, as well as very high bond, flexural and compressive strengths.
Uses would include, for example, furnace and firebox linings. Due to a high
resistance to
acid, the cement could be foamed and used as an intermediate insulation layer
as well as a hard
face layer in furnace linings. It can also be reinforced with carbon fibre and
used as fire proof thin
section cowling or panels for machinery, burners, work platforms, etc.
a. batching pre-processed metal oxide as indicated in the following formulae
or
b. manufactured in a simular process to limestone based cements by calcining
the
components and crushing them together.
Crushing would provide a greater fineness or greater surface area, making a
more
effective binder. The calcining of a phosphate usually produces a more
reactive pyrophosphate.
Formulators can choose to include phosphate during calcining or add later
during the crushing
phase. To reduce the likelihood of hygroscopic reaction in storage,
Mg(C18H3502)2 octadecanoic
magnesium stearic acid is added. This also increases cohesion and workability.
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Zirconium Silicate Cement Test Formulae
Based on the above criteria, a series of "zircon silicate cement" formulations
were tested,
each test being allocated a test number as "Zrx-XXa" where "x" is a number
referring to a subset
within the series, "XX" refers to the test number, and "a" refers to the kind
of initiator used
where "p" refers to phosphate, "pp" refers to phosphate - pyrophosphate, "s"
refers to sulfate, and
"c" refers to chloride. The tests are set out hereunder.
Zr3-OQu
Ingredients:
Constituents Content (% by weight) %Latitude
Fe304 0 0 to 15
Fe 0 0
Si02 0 0 to 25
A1203 10 5 to 50
A 1HPO4 15.5 10 to 35
*3Mg0 25 0 to 50
*4Mg0 6.5 0 to 50
MgSiF6 1 0 to 5
Mg(C18H3502)2 0 0 to 5
Na2B4O7-10HaO 2 0 to 10
ZrSiOa 40 15 to 75
TOTAL 100
Method:
An 0.01 g resolution balance was used to measure the dry components into a
mixing
beaker. A wooden spatula was used to mix in water with the dry ingredients
until the mix became
plastic. The mix was then stirred for a fiuther 3 minutes.
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The contents of the beaker were transferred into a mould and allowed to set
hard for a
period of 4 hours before being demoulded.
Result:
Within the first 15 minutes gelling had commenced and a small amount of
exothermic
heat was noted due to the accelerated setting caused by the (replaceable)
percentage of MgO*4.
Over the 3-day observation period, "test Zr3-OOa" gained very high strength.
Conclusion:
With the ability to control the set speed of this cement, it should be
possible to produce
extreme strength concrete with short optimum high early strength times. As
well as other
properties such as being refractory and waterproof, it is also sulphate and cl-
Aoride resistance,
enhanced by the very high achievable density.
Zr5-OOpp Foam
Ingredients:
Constituents Content (% by weight) %Latitude
Fe304 0 0 to 15
Fe 0 0
Si02 0 0 to 35
A1203 25 5 to 50
^1HPO4 15.5 0 to 35
HPO4 (** K4P207 (pyro)) 3 0 to 35
*3MgO 26.5 0 to 50
*4MgO 3 0 to 50
MgSiF6 0 0 to 20
Mg(C18H3502)2 0 0 to 5
NaHCO3 2 1 to 10
ZrSiO2 25 15 to 75
TOTAL 100
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plus
Fe9-OOpn Foam
Ingredients:
Constituent Content (% by weight) %Latitude
Fe304 35 17 to 75
Fe 0 Oto5
Si02 0 0 to 35
A1203 25 5 to 50
*3^1HPO 4 15.5 0 to 35
HPO4 (K4P207 (pyro)) 3 0 to 35
MgO 16.5 0 to 50
*4Mg0 3 0 to 50
MgSiF6 0 0 to 20
Mg(C1sH3502)2 0 0 to 5
NaHCO3 2 1 to 10
ZrSiOZ 0 0 to 50
TOTAL 100
Method:
An 0.01 g resolution balance was used to measure the dry components for each
mixture
into a separate mixing beaker. A wooden spatula was used to mix water in with
the dry
ingredients until in each case the mix became sufficiently fluid to cast. Each
mixture was then
stirred for a further 60 seconds.
The content of each beaker was transferred into a different mould and allowed
to set hard
for a period of 4 hours before being demoulded.
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Result:
Identical reaction in "test Zr5-OOpp and Fe9-OOpp" as the mixture was observed
to slowly
rise within 2 minutes of casting. Gelling occurred in 10 minutes, slight
exothermic heat was
noted until completely set at about 40 minutes. The aeration substantially
reduced the density of
the sample, however both samples still maintained high strength.
Conclusion:
Due to the very high refractoriness and adhesive nature of the zirconium
silicate foamed
cement, it would be useful as a fireproof spray applied insulation. Iron-based
foamed cement
according to the invention also has high strength properties, but may only be
suitable for
applications requiring refractory properties below about 800 C due to the
melting temperature of
iron. It would also be useful for the manufacture of aerated concrete blocks
and panels, without
the necessity to autoclave.
Cementitious mixtures according to the invention may be used as an alternative
to general
purpose cement (Ordinary Portland Cenient - OPC) used for concrete as well as
special
applications to utilize unique properties. For example, use may typically be
for mining, civil and
building construction. Specifically, applications could include, for example,
below ground and
underwater structure, foundations, footings, and pylons, as well as in extreme
chemical and gas
environments such as, for example, fuel cells, sewage treatment plants and
abattoirs. The
cementitious mixture may also have application in respect of industrial
flooring and pavements
where high magnetic attraction and low electrical potential is a requirement.
New development
for temporary machine anchoring, including horizontal and vertical robotic
movement will be
possible with the Iron Cement.
Suitable for fibre reinforced extrusion, capable of being pressed to any thin
wall shape.
Glass reinforced concrete application may benefit as the requirement for
"alkaline resistant" glass
fibre is eliminated. Due to its cohesive, high bonding nature this cement will
prove suitable for
spray (shotcrete - gunite) applications.
Although the invention has been described with reference to specific examples,
it will be
appreciated by those skilled in the art that the invention may be embodied in
other forms and
combinations thereof within the broad scope and ambit of the invention as
herein set forth.
